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Discussion Starter #1
hey folks. My battery keeps dying. Just about totally dead after 3 days. I went out and bought a decent multimeter, and I started pulling fuzes, testing the voltage and not getting anything because I was not doing it correct.

So I need to know what to do to find the drain. Is there a specific procedure I can follow to get to the bottom of this?

Do I read volts or amps?
Where should I apply the prongs?
Any help is greatly appreciated. I just bought a brand new Optima battery and a brand-rebuilt alternator. I hope the battery is not shot after being killed this much. . .
 

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Hmm. Try this, do you have a test lamp? Disconnect the + side of the battery. Connect one end of the test lamp to the battery cable and the other end to the positive post. Does the lamp light? If so, something is shorting out. Usually it's a door light or interior light that gets stuck on. You can pull fuses again until the light goes out, there's your trouble.

Good luck.

J. Boggs
 

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get your alternator tested ASAP....with that big a drain, it could very well be the diodes

basically gave away a car to someone with that prob...told him to disconnect the battery when not driving....he went to hook it up one day and the underdash wiring started smoking
 

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I agree, I'd do it just a little bit differently though. I'd pull the negitive cable and use a meter. The light will only light if the drain is enough amps to light up the light, which it may or may not be. That would be testing on volts with the meter set to 20 volts. Then start pulling fuses one at a time until the drain goes away, or the voltage drops to 0, (esentialy the same thing).

If this doesn't get anywhere, no draw, then I'd suspect the battery. To check it at home, just disconnect it for the same ammount of time that it would normally take to be dead, and re-connect it. If it won't start the car then it has to be the battery , just by default.
 

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First place to look is the cigarette lighter. If your glove box , trunk or hood has a light make sure it goes out when you close it. Also stereo equipment and electronic chokes might drain power invisably.

Failing that, pull a fuse out and when your pushing it back in look and see if it sparks. Watch the one that the interior lights work off of with the door open and the door closed. You should be able to see the difference. Make sure your gauges go off when you have the key off and back on when you turn the key on.

You should also be able to see a spark when you touch the battery cable to the battery. Be carefull when you do this, if the battery gets hot it will vent hydrogen but if the battery is not hissing its safe. People blow up betteries when they try to use jumper cables and cross the cables and put a dead load on the battery then take a cable off and back on wondering why the car won't jump start. I guess you could make the sparks over by the solinoid to be safer. Anyhow you should be able to see the spark of a short that can bring a battery down in 3 days. Now all you need to do is start unplugging things till you can make the spark stop happening. Once you narrow down where to look you should be able to find it.
 

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If you want a simple fix, check out the voltage regulator. This is the #1 overlooked item and it is usually the #1 cause of the problem you described.

Deathman68
 
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OK here is a way to check with a multi meter you need a meter with a amp reading set meter to amp reading, amp reading is in series meaning that you complete a circuit with it so disconect one of the battery cables now take the meter and complete the circuit from the battery to the cable that you disconected current will follow if short somewhere and the meter will read it now start pulling fuses one at a time while someone watches the meter the meter changes quite a bit then you have found you drain if it doesnt then start unhooking wires one at a time then hook them back before unhooking another you will be eliminating until you find the right one. I have done a lot of electrical repair in the past best way always to me is to eliminate each circuit. good luck Leroy
 
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